It is narrated from Hazrat Ikrimah (may Allah have mercy on him): When this verse was revealed «إِلَّا تَنْفِرُوا يُعَذِّبْكُمْ عَذَابًا أَلِيمًا وَيَسْتَبْدِلْ قَوْمًا غَيْرَكُمْ» , the hypocrites said: "There are some people who did not go out for jihad, so have they perished?" Whereas there was a group that stayed behind to acquire knowledge of the religion «لِيَتَفَقَّهُوا فِي الدِّينِ» , and about them Allah said «وَالَّذِينَ يُحَاجُّونَ فِي اللَّهِ مِنْ بَعْدِ مَا اسْتُجِيبَ لَهُ» .